package map;


import java.util.Collection;
import java.util.HashMap;
import java.util.Map;
import java.util.Set;

/*
    Map的遍历，支持三种遍历方式：
    1.遍历所有的key
    2.遍历所有的键值对
    3.遍历所有的value(相对不常用)
 */
public class MapDemo2 {
    public static void main(String[] args) {
        Map<String,Integer> map = new HashMap<>();
        map.put("语文",100);
        map.put("数学",95);
        map.put("英语",99);
        map.put("体育",80);
        map.put("化学",70);

        System.out.println(map);

        Set<String> ketset = map.keySet();
        for (String key:ketset){
            System.out.println("key:"+key);
        }

        Set<Map.Entry<String,Integer>> entrySet = map.entrySet();
        for (Map.Entry<String,Integer> e:entrySet){
            String key = e.getKey();
            Integer value = e.getValue();

            System.out.println("key:"+key+",value:"+value);
        }

        Collection<Integer> values = map.values();
        /*
        for (Integer value : values){
            System.out.println("values:"+value);
        }*/
        values.forEach(System.out::println);

        map.forEach((k,v)->{
            System.out.println(k+":"+v);
        });


    }
}
